It is possible to make the caption and/or the author visible on the thumbnails of a Gallery, but how can I make it possible on the Lightbox ?
I would like to have the caption visible under the image and, even more if possible, with a link to another page or anchor (for example an item shop page
We don’t currently support displaying captions and authors on a single Image lightbox.
However, you could build this by using a Modal. Simple drop in an Image as the modal trigger, and then place whatever content you want inside the Modal content dropzone (in your case just an Image and some Text).
Hope that helps 
Ben it’d be great if you could please add captions to the lightbox.
If you’re focusing into an image - it’s logical that you’re interested in what it is
Yes, also looking for this–Lightbox showing caption below image.
yes please
Thanks for all the feedback, I totally get why people want captions inside the built-in Lightbox. However, it’s actually quite complex to implement 
The current Lightbox is designed to be fast, and minimal, which is why it doesn’t support metadata in the modal view… that said, we’re working on a more advanced gallery system written from the ground-up with meta data support, zooming, panning and a lot more control over how images are displayed.
It’ll ship as a separate, pro-level component in the Store, aimed at Photographers that need ultimate control. It’s already in active development. It’s coming together nicely and it should be available before the end of the year 
Cheers!
Thank you ! That’s a pretty good news indeed ! Please include the possibility to have links to external url but surely to internal url, typical usage for me would be to have a photo in the gallery with a « Buy in the store » link to my own shop in the comment/description below it.